Chain guard for overhead hoists



Jan. 21, 1958 T. WALKER 2,820,662

CHAIN GUARD FOR OVERHEAD HOISTS Filed Oct. 4, 1956 2 Sheets-Sheet 1 INVENTOR THOMAS WALKER ATTORNEY Jan. 21, 1958 WALKER 2,820,662

CHAIN GUARD FOR OVERHEAD HOISTS Filed Oct. 4, 1956 2 Sheets-Sheet 2 1;INVENTOR l7 THOMAS WALKER ATTORNEY United States Patent CHAIN GUARD FOROVERHEAD HOISTS Thomas Walker, Chester, Pa.

Application October 4, 1956, Serial No. 613,992

Claims. (Cl. 294-78) The present invention has reference to guards orprotective means used particularly in connection with overhead hoists orsimilar heavy duty apparatus.

Overhead hoists or cranes usually include a traveller or block fromwhich are suspended a plurality of chains, usually four in number, to besecured at their lower ends to the heavy and bulky load to be elevatedand transported. In instances where the load is extremely heavy, or isof unusual size, it is customary to use all of the chains, attached inspaced relationship at their free ends to the load in order that thelatter may be properly balanced for lifting or transportation purposes.However, it frequently occurs that two of the depending chains aresuflicient to support the load, in which event the free ends of theunused chains are usually temporarily attached, as by their hooks, tothe ring or other part of the crane so as to be out of the way and notto interfere with the free and proper operation of the crane itself. Itsometimes happens, however, that the free ends of these unused chainsbecome accidentally detached from the overhead support, thus liberatedgiving rise to injury to nearby workmen or possibly seriouslyinterfering with the proper operation of the work.

The device of the present invention is developed to guard against thisdanger, and includes means whereby dropping of the chain ends from theirsupport to the danger zone will be avoided.

A further object of the invention is to provide a guard of suchconstruction that it may be quickly and easily attached to overheadcranes or other similar types of machinery of present day use and whichwill effectively hold the free end of a suspended chain from dropping tosuch position as might cause danger of injury to workmen or interferencewith the proper operation of the mechanism.

A further object of the invention is to provide a guard of extremelysimple construction which may be manufactured at low cost, which may beattached to modern cranes quickly and easily and without the exercise ofspecial skill or training, which will prove highly effective in itsoperations and which may be readily detached from the crane or othermachine when desired. With the foregoing objects in view, together withothers which will appear as the description proceeds, the inventionresides in the novel construction, combination and arrangement of parts,all as will be described more fully hereinafter, illustrated in thedrawing, and particularly pointed out in the claims.

In the drawing:

Fig. l is a perspective view of a conventional overhead crane structureillustrating the application thereto of guards embodying my invention,

Fig. 2 is an enlarged detail side elevation showing the guards inassociation with the crane and in the position they will assume whenattached to the chain lengths not m use,

Fig. 3 is an end elevation of the device shown in Fig. 2, taken on line3-3 thereof, and showing the free end 2,820,662 Patented Jan. 21, 1958of the suspended chain confined within the guard sleeve,

Fig. 4 is a side elevation of one of the guards showing the hook at thefree end of the chain engaged with the rim of the sleeve,

Fig. 5 is a transverse sectional view taken substantially on line 55 ofFig. 4, and

Fig. 6 is a side elevation of the invention showing the hook of the freeend of the chain in a slightly different position.

The invention is here illustrated in connection with a standard or wellknown type of overhead crane, but it will be understood that theinvention may equally as efiectively and efliciently be used inconnection with other types of machinery; in fact, it may be adequatelyused in connection with any type of machinery of this general characterwhere free swinging chain ends may be a detriment to safety.

In Fig. l of the drawing, the overhead crane or traveller is representedgenerally at 6 and includes a relatively heavy block or sheave as shownhaving an attaching ring or loop 7 depending from its lower end. Thisring has secured thereto the upper ends of the supporting chains 8,being attached to the ring or loop either by hooks or by rings 9 asindicated. The lower or free ends of the chain 8 are provided with hooks10 to be engaged with the load for the support of the latter. Ininstances where the load is extremely heavy, or where it is bulky, allfour of the chain lengths are used in order to either equally distributethe weight of the load or to properly balance the latter in theoperation of the crane. However, it frequently occurs that only two ofthe depending chains need be used in handling the load, in which eventthe. remaining or unused chain lengths are doubled upon themselves asshown in Fig. 2 with the hooks 10 at their free ends engaged either inone of the upper links of the chain or in the ring which attaches it tothe ring or loop 7 of the crane. It is usual that the hooks 10 are ofconsiderably greater transverse dimension than the links of the chain 8.

A guard of my invention is provided for each of the chain lengths not inuse. This guard comprises an elongated sleeve made of suitablerelatively thin metal indicated at 11 having spaced arms 12 at its upperend to straddle the ring or loop 7, a bolt 13 passing through suitableopenings in the arms 12 above the ring or loop 7 to retain the guard insuspended relationship from the ring 7. A wing nut 14 may be engagedwith the end of the bolt to secure the same removably upon the dependingring 7. The sleeve 11 is cut away for most of its length but near itslower end is tapered or restricted to provide a neck as at 15. Thisrestricted portion is free of the sleeve at one side and is providedwith an outwardly directed flange 16 through which a bolt 17 passes andextends through a similar flange 18 on the body of the sleeve; a wingnut 19 may engage with the threads of the bolt to hold the restrictedneck portion in proper closed position. The restricted neck portion isof sufiicient transverse diameter to permit of the accommodation of thechain 8 doubled upon itself, but is of less transverse diameter at itslower end than the transverse diameter of the hook 10 at the free end ofthe chain. The upper end of the restricted neck portion 15 of the sleeveprovides a ledge 20 as shown.

It will be understood that a guard sleeve of the type here described isprovided for each of the chain lengths to be guarded. The restrictedneck portion of the sleeve 11 may be opened by removing the bolt 17 sothat the chain may be passed to the interior of the restricted neckportion laterally, after which the bolt would be applied and the wingnut tightened, thus confining the chain within the sleeve. With the hook10 engaged either in one of the links of the chain or with the ring orloop withits back against the. trough of the sleevel la soQthat in f ilfief 'h kfw g i h t. ne se wi he. led eas shown in Fig. 14 or will"wedge'li'n f the. restricted 'neck portion 115" of-th'e sleeve 'asinFig, 3. 1 7

,m 'SIW F Q iQ Q it ap a entha h f e end 'of the chain doubleduponi'tsfelf will be positively prevented from dropping b'eygnd therestricted neck por tion ZlS of the guardfeither by engagementofthe'hook10 over the shoulder or ledge 29 of the sleeve or within the restrictedneekporti'on of the sleeve. The use of the guard thus insures againstany injury 'to 'adjacen't workmen orinterference with theproperoperation of the crane y whipp c fi et-1 winins chains s hasheretofore'occnrred. V

It will be o' bservedythat the guard Jispso constructed that it may "beeasily and quicklyattached to various types of 2 i ft is la m L s".simple ope a io and without thefexerciseof special skill or knowledge,yet at all times absolutely preventsthe'chain end 'from becomingdetached; Being made of re'lajively steel fthe guard y h sfl te nle methdsr nd; alt m n mumofxexpense, atth esarne "time proving, at "timesefiective'in carrying out the purposes forwhieh i't is designed. Y V

-1. In combination, a'movable supporthaving the upper end o f a treeswinging chainpermanently. attached thereto with a hookat'the free endof the chain of greater transverse dimension than said chain; of asleeve swingingly engaged at its upper end with said support independing relationship therewith and being of less length than thechain, a restricted neck portion at the lower end of said sleeve looselyenclosing said chain, said restrictedportion of said sleeve being ofless diameter than the transverse dimension of said hook. i

Asgard-far: 355 16 s in n ho s h l w ic is attached at its upper end toa movable support and having a hook at the-tree'end thereof,- comprisinga sleeve 0t less length than; the chain suspendedinparallel relationshipwith the upper end of said chain and enclosing a depending portionthereof; said-'hook -being of greater a hook from passing .therethrough.

transverse dimension than said chain, the lower end of the sleeve havinga restricted portion of a diameter less than the transverse dimension ofthehook to prevent said 3. Aguard as set forth in-claim 2, wherein therestricted portion of lthe. sleeveis open at one side, flanges on the,

: the chain andof lessglength than the rlatter the lowen end of J the.sleevetfhaving, a restricted; neck portion and being; of. a diametersmaller thauthe transverse dimension of the hook to. prevent; the hook.;from passing therethrough.

Noe i mes i ed

